1. Field of the Invention
The present invention relates to two-piece multi-lead connectors including a housing and terminal insert. More particularly, it relates to a new and improved two-piece connector with a terminal mounting means on the insert which permits only properly crimped terminals installed in the proper orientation on the insert to be successfully inserted into the connector housing.
2. Description of the Prior Art
Two-piece connectors for terminated wire leads, generally comprising a connector housing and a telescopically received terminal insert or carrier having terminated wire leads maintained thereon are known. Two-piece assemblies are desirable because of their ease of assembly and modularity. When the connector must accommodate and manage a plurality of terminated leads, special considerations arise. Each terminated lead, for example, in a pin and socket mating arrangement, has an associated force that is required to mate the terminal with another corresponding component, i.e. in both insertion and withdrawal directions. When a connector contains several leads, the cumulative insertion and withdrawal forces associated with mating the connector to another component can be very high. In these multi-lead two-part connectors, the terminal insert member must be reliably retained in the connector housing during mating and unmating of the connector, to prevent the connector from coming apart in use.
For some applications, for example in contaminated environments, high mating forces for each terminal are desireable or required. More particularly, high mating forces for a given terminal can ensure a sufficient wiping action between the terminal and mated contact to remove oxide coatings or other contaminants from the contact surfaces during mating to provide a gas-tight seal necessary for a reliable electrical connection. In these applications the terminated leads must be reliably retained in the terminal insert so that terminal push-out or pull-out does not occur during coupling or uncoupling of the connector.
Terminal retention is also important in other rugged environments where it is forseeable that the connector will be unmated by an operator pulling on the wires rather than the connector housing, or tripping over them, or the like. In automotive applications, terminal retention is required despite unforeseen circumstances or environmental conditions.
Generally in rugged environments, crimp-type terminals are preferred because the mechanical gripping connection between the metal terminals and wire leads in the crimp section, is generally stronger than found with other types of terminal to wire connections, for example, in insulation displacement type terminals. Nevertheless, engagement with a conductive wire in a crimp-type terminal is satisfactory only for a given, rather narrow range of terminal compression about the wire. If the wire engaging crimp portion is insufficiently compressed, the necessary low resistance electrical connection between terminal and wire will not be realized. A ready visual indication of improper height of the crimp portion, i.e., a defective crimp termination is desired so that defective wire leads are detected before the connector is fully assembled.
Further, some connector arrangement has terminals with mating portions located off center from the axis of the remaining terminal body. Other terminals have asymmetric cross sectional configuration, such as blade or flag-type terminals. For these arrangments, the relative angular orientation of the terminal with respect to its dielectric housing is crucial for successful connector operation. A ready visual indication of angular terminal orientation is desired.